Project Summary Psychotic disorders are serious and debilitating mental illnesses that incur substantial suffering for patients and present major challenges to our health care system. Given that few individuals achieve recovery after the onset of a psychotic disorder, there is increasing interest in the early identification and prevention of psychosis. Psychotic disorders are typically preceded by a prodromal phase characterized by functional decline and subtle attenuated symptoms that progressively worsen over the course of several months to years. This period is of interest both as a window for investigating processes involved in disease onset and as a potential point of intervention and prevention. The stress-vulnerability model remains one of the leading theories on the origins of psychosis. However, dysfunctional HPA axis activity and heightened stress reactivity alone only modestly predicts conversion to psychosis among CHR youth and has not led to breakthroughs in prevention. To develop novel targets for early intervention, the current project aims to test the central hypothesis that abnormalities in emotion regulation (i.e., the ability to use strategies to decrease the intensity or frequency of negative emotion) are a vulnerability factor that increases risk for developing a psychotic disorder. We propose to conduct a comprehensive evaluation of emotion regulation through the lens of Gross? extended process model of emotion regulation. This model proposes that emotion regulation involves a series of stages, including: identification (i.e., detecting emotion and determining whether to regulate), selection (i.e., choosing a strategy), and implementation (i.e., executing the selected strategy). Our preliminary data in adults with schizophrenia (SZ) indicates that abnormalities at each of these stages contribute to state fluctuations in hallucinations and delusions. The current application proposes to extend this finding to 50 CHR youth and 50 healthy controls who will complete a cross-sectional evaluation consisting of a multimodal battery of emotion regulation laboratory tasks (behavior, electrophysiology, eye tracking, pupillometry) and 6 days of ecological momentary assessment (EMA) that will be submitted to mathematical modeling. This data will be used to complete the following specific aims: 1): To evaluate the stress-vulnerability model and test the hypothesis that attenuated psychotic experiences are temporally preceded by abnormalities in autonomic nervous system reactivity; 2) To define which stages of emotion regulation are abnormal in CHR youth and identify moderators of each stage; 3) To identify whether abnormalities at each of the stages of emotion regulation are predictive of psychosis risk and determine whether the combination of emotion regulation abnormalities and stress reactivity will predict psychosis risk more so than either variable alone. Findings resulting from this study will benefit early identification and prevention efforts by identifying specific emotion regulation processes that can be targeted in psychosocial interventions. Such interventions have proven effective for treating other disorders, but have not yet been evaluated in the schizophrenia-spectrum to determine efficacy for prevention.